Allergic conditions in the past have been treated with a variety of drugs including those characterized as 1-alkyl-4-(5H-dibenzo[a,d]cyclohepten-5-ylidene)piperidines.
Prior to the present invention, it was known that the compound cyproheptadine of the structure ##SPC1##
Was an active antihistaminic and antiserotonin agent and was therefore useful in the treatment or relief of certain allergic conditions. This is disclosed in U.S. Pat. No. 3,014,911, E. L. Engelhardt, which patent was issued Dec. 26, 1961.
The novel 10-oxo or -hydroxy compounds of my invention are distinguished from the prior art patented compounds by their enhanced antihistaminic activity and their diminished activity with respect to serotonin antagonism and central and peripheral anticholinergic activity as measured in standard laboratory test animals.